New research from the Carnegie Institution for Science says offshore wind farms situated in the North Atlantic have the potential in the winter to provide sufficient energy to meet all of civilization’s current needs.
Considering wind power is very seasonal, the researchers note that in the summer, these wind farms could generate only enough power to cover the electricity demand of just Europe, or possibly the U.S.
The research, published by Proceedings of the National Academy of Sciences, was conducted by Carnegie’s Anna Possner and Ken Caldeira. It highlights the considerable opportunity for generating wind power in the open ocean, particularly the North Atlantic.
“Are the winds so fast just because there is nothing out there to slow them down? Will sticking giant wind farms out there just slow down the winds so much that it is no better than over land?” Caldeira asked.
Most of the energy captured by large wind farms originates higher up in the atmosphere and is transported down to the surface where the turbines may extract this energy. Other studies have estimated that there is a maximum rate of electricity generation for land-based wind farms and have concluded that this maximum rate of energy extraction is limited by the rate at which energy is moved down from faster, higher-up winds, according to the researchers.
“The real question is,” Caldeira continued, “can the atmosphere over the ocean move more energy downward than the atmosphere over land is able to?”
Possner and Caldeira’s modeling tools compared the productivity of large Kansas wind farms to massive, theoretical, open-ocean wind farms and found that in some areas, ocean-based wind farms could generate at least three times more power than the ones on land.
In the North Atlantic, in particular, the drag introduced by wind turbines would not slow down winds as much as they would on land, the researchers found. This is largely due to the fact that large amounts of heat pour out of the North Atlantic Ocean and into the overlying atmosphere, especially during the winter. This contrast in surface warming along the U.S. coast drives the frequent generation of cyclones, or low-pressure systems, that cross the Atlantic and are very efficient in drawing the upper atmosphere’s energy down to the height of the turbines.
“We found that giant, ocean-based wind farms are able to tap into the energy of the winds throughout much of the atmosphere, whereas wind farms onshore remain constrained by the near-surface wind resources,” Possner explained.
According to the researchers, the huge wind power resources identified in the study can provide strong incentives to develop lower-cost technologies that can operate in the open-ocean environment and transmit the electricity to land.